Design integration of hosted payloads — Do no harm analysis

Concerns in integrating a Hosted Payload (HP) on a Host Space Vehicle (HSV) include potential propagating interface failure modes to the HSV that could jeopardize the primary mission. Failure isolation of the HSV power bus with fuses, relays, and disconnecting “non-essential loads” during a bus under-voltage survival mode is a normal design practice. Experience on recent hosted payload projects indicates this practice is not sufficient to preclude all sources of harm that a HP can create for an HSV. In a broader sense, “harm” is the result of negative effects on successful mission performance from either the HP or HSV. Unnoticed gaps between the HSV and HP in requirements, capabilities and environments are more frequent in Hosted Payload projects as the HP and HSV are developed separately. Common themes resulting in increased risk include insufficient information sharing between the HSV and HP teams; lack of knowledge of HSV requirements, configuration, mission operations and environments during HP development. Procedures and checklists were created for identifying and eliminating potential incompatibilities between the HSV/HP interfaces. A list of critical analyses to ensure interface compatibility and successful mission performance was also developed.